Sidney Boyer Let’s be honest—carbon markets feel a bit like the Wild West right now. One day you’re reading about a forestry project that’s saving the planet, the next you’re seeing headlines about credits being double-counted or, worse, phantom trees that never existed. It’s messy. But here’s the thing: the mess isn’t a reason to walk away. It’s a reason to get sharper.
For anyone buying carbon credits—especially nature-based offsets—due diligence isn’t just a box to tick. It’s your survival kit. Because when you strip away the glossy brochures and the drone footage of lush canopies, you’re really investing in a promise. And promises, well… they need verification.
Why nature-based offsets are suddenly under the microscope
Nature-based solutions—think reforestation, mangrove restoration, soil carbon, avoided deforestation—are the darlings of the voluntary carbon market. They promise co-benefits like biodiversity and community livelihoods. Who doesn’t love that? But the scrutiny has intensified. Why? Because a few high-profile scandals (I won’t name names, but you know the ones) have made buyers skittish.
In fact, a 2023 study from the University of Berkeley found that around 30% of credited rainforest offsets showed no evidence of additional carbon storage. That’s a gut punch. It doesn’t mean all projects are bad—far from it. But it does mean that the era of “trust me, bro” due diligence is over.
So, what does real due diligence look like? It’s not just checking if the project has a certificate. It’s peeling back layers. It’s asking awkward questions. It’s getting your hands dirty—metaphorically, and sometimes literally.
The baseline problem: what would have happened anyway?
Here’s the core question that keeps carbon accountants up at night: additionality. Would this forest still be standing if your money hadn’t shown up? Would that degraded land have been restored anyway? If the answer is “yes, probably,” then your credit is worthless.
Assessing additionality is less about math and more about narrative. You have to reconstruct a counterfactual world. That’s tricky. A robust due diligence process digs into the project’s baseline methodology. Ask for the raw data. Look at the reference region. Check if the baseline was inflated—some projects do that to create more credits. It’s a known trick.
And here’s a subtle point: additionality isn’t binary. It’s a spectrum. A project might be partially additional. Maybe it would have happened, but slower. Or with less quality. Your job is to figure out where on that spectrum it sits—and price accordingly.
Leakage and permanence: the two sneaky cousins
You’ve heard of leakage, right? That’s when protecting one patch of forest just shifts deforestation to another patch nearby. It’s like squeezing a balloon—the air just moves. Good due diligence maps the leakage zone. It checks satellite imagery beyond the project boundary. It talks to local communities about their fuelwood needs.
Permanence is the other beast. A tree planted today might be cut down in 30 years. Or burned in a wildfire. Or killed by pests. So how do you guarantee storage for 100 years? You can’t, honestly. What you can do is look for buffer pools—a shared insurance fund where a portion of credits from every project is held back. If one project fails, the buffer covers it.
But not all buffers are created equal. Some are well-capitalized; others are basically a spreadsheet and a prayer. Check the buffer pool’s historical performance. Have they actually paid out? That data is rare, but it’s gold when you find it.
Co-benefits: nice to have, or essential?
Let’s pivot for a second. Biodiversity. Water filtration. Local jobs. These aren’t just fluffy add-ons. They’re often the difference between a project that survives and one that collapses. If a community doesn’t benefit from the project, they have no incentive to protect it. That’s just human nature.
During due diligence, don’t just read the co-benefit report. Verify it. Talk to independent NGOs on the ground. Look at grievance mechanisms—how do locals file complaints? A project with a functional grievance process is a green flag. A project that says “no complaints ever” is a red flag. Seriously, no complaints ever? In any community? Unlikely.
Here’s a quick checklist you can use when evaluating co-benefits:
- Are the claimed community benefits backed by third-party audits?
- Is there a transparent revenue-sharing agreement with local landowners?
- Does the project align with national biodiversity strategies?
- Are there mechanisms to adapt to climate change impacts (e.g., drought-resistant species)?
The registry rabbit hole: where credits actually live
You’d think tracking a digital credit would be simple. It’s not. Each credit has a serial number, but the trail can get murky. The big registries—Verra, Gold Standard, American Carbon Registry—have their own rules. But even they have faced criticism for lax verification.
Your due diligence should include a registry deep-dive. Check the issuance date. Check the vintage. Check if the same credit has been retired or if it’s still floating around. And here’s a pro tip: look for serial numbers that have been re-issued after a project revision. That’s a red flag for potential double-counting.
Also, beware of “zombie credits”—old credits from projects that are no longer active. They still trade on some platforms. It’s legal, but it’s not great for your ESG story. A good due diligence process filters these out automatically.
Technology is your friend (but not a silver bullet)
Satellite imagery. LiDAR. AI-driven biomass models. Blockchain for traceability. The tools are getting better, no doubt. You can now monitor a forest’s health in near real-time. That’s incredible. But here’s the catch: technology measures carbon, not intent. It can tell you a tree is there, but not why it’s there.
So use tech for screening, but pair it with on-the-ground verification. That might mean hiring a third-party auditor who actually visits the site. Or doing remote interviews with project staff. It’s slower. It costs more. But it catches the stuff that satellites miss—like a community that’s secretly unhappy, or a management team that’s cutting corners.
A practical due diligence framework (in 5 steps)
Alright, let’s make this actionable. Here’s a framework I’ve seen work well, especially for mid-sized buyers who don’t have a massive ESG team.
- Desk review – Pull the Project Design Document (PDD). Read it twice. Cross-check the carbon accounting against the methodology.
- Registry check – Verify the credit status, issuance, and retirement history. Look for any anomalies.
- Independent audit – Don’t rely on the validator that the project chose. Commission your own, or at least review the validation report with fresh eyes.
- Field verification – This can be remote or in-person. Use a mix of satellite data and local interviews. Look for signs of leakage.
- Ongoing monitoring – Due diligence isn’t a one-time event. Set up quarterly reviews. Track the project’s performance against its own milestones.
That’s it. It’s not glamorous, but it works. And honestly, it’s what separates the buyers who sleep well at night from those who end up in the news.
Pricing signals: when cheap is too cheap
You know the old saying—if it looks too good to be true, it probably is. The same applies to carbon credits. If you see nature-based offsets at $2 per tonne, run. Not walk. Run. Because the cost of actually doing this right—land acquisition, monitoring, community engagement, verification—usually lands between $10 and $30 per tonne for quality projects.
That doesn’t mean expensive always equals good. But price is a signal. A very cheap credit often means corners were cut somewhere. Maybe the baseline was padded. Maybe the permanence buffer is underfunded. Maybe the project is just a paper project with no real-world impact.
| Price Range (per tonne) | Typical Signal | Due Diligence Priority |
|---|---|---|
| < $3 | High risk of over-crediting | Extreme scrutiny or avoid |
| $3 – $10 | Mixed quality; check additionality | Full framework recommended |
| $10 – $30 | Likely credible, but verify | Standard framework |
| > $30 | Premium for co-benefits | Focus on co-benefit verification |
But price alone isn’t the answer. You need to triangulate price with project age, location, and methodology. A newer project in a high-risk region might be priced higher because of the risk premium. That’s fine, as long as you understand what you’re paying for.
The human element you can’t ignore
Here’s the part that doesn’t show up in spreadsheets. Projects are run by people. And people have incentives. Sometimes those incentives align with yours—sometimes they don’t. A project developer might be more interested in maximizing credit issuance than in actual carbon sequestration. It happens.
That’s why relationship matters. Talk to the project team directly. Ask them about their biggest challenges. See if they’re candid or defensive. A team that openly discusses their failures is more trustworthy than one that only shares sunshine and rainbows. You’re looking for intellectual honesty, not just polished marketing.
And don’t forget the local community angle. If you can, talk to a few people who live near the project. Not the community leaders—the regular folks. Do they feel the project is helping? Do they feel heard? Their answers will tell you more than any audit report ever will.
Regulatory shifts on the horizon
The voluntary market is evolving fast. The Integrity Council for the Voluntary Carbon Market (ICVCM) has released its Core Carbon Principles. The VCMI has its Claims Code. And
